GIA4699778 Drawing depicting the transformation of a helmet into an underwater mask. The visor is used to hold the repiratory tube - in ??????De Ingeneis??????by Mariano di Jacopo, said Il Taccola 15th century. by Mariano di Jacopo (detto il Taccola) (1382-c.1453) (after); Private Collection; (add.info.: Drawing depicting the transformation of a helmet into an underwater mask. The visor is used to hold the repiratory tube - in ??????De Ingeneis??????by Mariano di Jacopo, said Il Taccola 15th century.); by Giancarlo Costa; Italian, out of copyright.